1892. ] NEW YORK ACADEMY OF SCIENCES 43 
mergence which amounted to 100 feet at Croton and 340 feet at 
Schenectady. Upon the re-elevation of the land they were 
much eroded by the Hudson River. 
The section involved is 
Fine stratified yellow sand, 
Yellow clay, 
Blue clay. 
They are underlain by modified drift, till or bed-rock. At the 
mouths of the tributary streams deltas are found. The clays 
are from 10 to 243 feet thick, and the blue is weathered to y ellow 
in the upper portion of the bank. (See H. Ries, Trans. N. Y. 
Acad. Sci., Nov. 1891.) 
Clays of the Delaware and Susquehanna Watershed. 
At Breesport, near Elmira, is a bank of blue clay rising from 
the valley to a height of 50 feet. It was formed when the 
valley was dammed up. Subsequently the stream has eroded it 
so that now all that remains is a narrow strip which forms a 
sort of a terrace along the side of the valley. 
A similar deposit is found at Newfield, south of Ithaca. A 
moraine crosses the valley a mile or two south of it. 
An interesting bed of clay occurs at Levant, Chautauqua 
County. It occupies several acres and is probably of post-gla- 
cial age. The section as determined by artesian well borings is: 
Yellow sand . ‘ - . : 4 feet. 
Quicksand : : 5 4 ; 4 inches. 
Yellow clay : - . : - 5 feet. 
Blue clay : 3 : : . 70 feet. 
Hardpan . : ; - . - — feet. 
Total thickness : ; ; 83 feet. 
The owner of the clay bedinformed me that leaves were often 
found between the layers of the clay at a depth of 15 or 20 feet. 
Staten Island Clays. 
The clays of Staten Island are chiefly Cretaceous, as proven 
by the fossils found in them. (A. Hollick, Trans. N, Y. Acad. 
Sci., Vol. xi.) The chief outcrops are at Kreischerville, Green 
Ridge and Arrochar, Besides the clay there are several kaolin 
deposits. 
In many instances the clays have been much disturbed by the 
passage of the ice over them, and in some cases the sections 
show overthrown anticlines, as on the Fingerboard Road at 
Clifton. 
Mr. W. Kreischer informed me tbat the clay at Kreischerville 
curs in isolated masses or pockets in the yellow gravel and 
